Android interface clarification

See more:

Java

Android

From this code:

SQLiteDatabase db = this.getWritableDatabase();
Cursor rs = db.rawQuery("SELECT * FROM mytable", null);

db.rawQuery returns a Cursor which is an interface and it has a method called getCount(). I wonder how does this method gets the number of records without seeing its implementation. The method rawQuery does not also explain where it is coming from.

Please help me. I do understand how interface works but I think I am missing something. Thanks in advance.

What I have tried:

I visited the SQLiteDatabase.class but most methods just throws RuntimeException.